Among hearing loss, those that result from labyrinthine (cochlear) or retrocochlear (8th cranial nerve) causes are called sensorineural hearing loss. Causes of sensorineural hearing loss are varied, and include, for example, Meniere's disease, drug-induced inner ear disorders (inner ear disorders due to anti-cancer agents such as aminoglycosides and cisplatin), viral inner ear disorders, purulent inner ear disorders, temporal bone fracture and acoustic nerve tumor. Sudden deafness, senile deafness and noise deafness are also among the sensorineural hearing loss. Noise deafness develops when the inner ear is injured by loud noises from chain saws, internal combustion engines, heavy equipment, guns, airplanes and the like, and is associated with gun firing, snow mobiles, air flight, rock concerts and the like.
Various factors are considered to cause sensorineural hearing loss, in which acute immune reactions responses are known to cause permanent hearing loss (Satoh H. et al., Laryngoscope. 2002 September; 112(9):1627-34). In immune responses in the cochlea caused by the injection of keyhole limpet hemocyanin (KLH) into the inner ear or the subarachnoid, it has been reported, TNF-α and IL-1β have been expressed, TNF-α causes an aggravated disease in the cochlea, and TNF-α inhibitors can partially suppress hearing loss, ibid. However, there are no reports up to now on the contribution of IL-6 to sensorineural hearing loss.
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Satoh H. et al., Laryngoscope. 2002 September; 112(9):1627-34